Answer:240 rotations
Step-by-step explanation: 1 rotation/45 seconds * 60 seconds / minute * 60 minutes / hour * 3 hours = 3600*3/45 = 240 rotations
An airplane is flying overhead at a constant elevation of 4090 ft. A person is viewing the plane from a position 3010 ft from the base of a radio tower. The airplane is flying horizontally away from the person. If the plane is flying at the rate of 700 ft/s, at what rate is the distance between the person and the plane increasing when the plane passes over the radio tower
Answer:
415 ft/s
Step-by-step explanation:
I've attached a diagram showing the triangle formed between the plane, the person and the radio tower.
From the attached diagram, x represents the position between the person and the position on the ground directly below the airplane while s represents the distance between the person and the plane.
The constant elevation remains 4090 ft while the value of x and s varies with time.
Thus, x varies with respect to time as dx/dt while s varies with respect to time as ds/dt.
Now, we are told that the plane is flying at the rate of 700 ft/s. This means that; dx/dt = 700 ft/s
Now we want to find the rate at which the distance between the person and the plane is increasing when the plane passes over the radio tower.
This means that we want to find ds/dt when x = 3010 ft
From pythagoras theorem if x = 3010 ft and the Elevation remains 4090 ft, we can find s as;
s = √(4090² + 3010²)
s = √25788200
s ≈ 5078.21 ft
Since we want to find ds/dt at x = 3010 ft, from the diagram, we can say from pythagoras theorem that;
x² + 4090² = s²
Differentiating x and s with respect to t, we have;
2x(dx/dt) = 2s(ds/dt)
2 will cancel out to give;
x(dx/dt) = s(ds/dt)
ds/dt = (x/s)(dx/dt)
Plugging in 700 for dx/dt, 3010 for x and 5078.21 for s, we have;
ds/dt = (3010/5078.21) × 700
ds/dt ≈ 415 ft/s
mental math again 60x40x2
Answer:
the answer is 4800
Answer:
What is mental math?
Mental math is definitely what it sounds like—doing math in your head. But it’s also more nuanced than that. Being good at mental math tricks doesn’t mean that you’re able to solve 8974387 x 396 in your head instantly; while cool, that wouldn’t be very practical for daily life. So what does mental math mean?
It really just means being able to calculate in your head. It doesn’t mean you can solve every type of problem every time, nor is it a skill that you either “have” or “don’t have”; it’s a skill that you can learn, practice, and improve so that you can solve a bigger range of problems. And mental math certainly doesn’t have to be entirely in your head, either. Jotting down the numbers you need to remember to give you a head start (no pun intended), or writing down your solutions at each “step,” does not negate the “mental”-ness of the math.
Is mental math useful?
Ask this question again next time you’re trying to figure out a tip or doing any kind of construction or home improvement project! And, in addition to handy practical uses, knowing how to do mental math can also just keep your brain sharp and curb your reliance on calculators. Because, come on, doesn’t it feel good to reach for a calculator only to realize, “Wait, I don’t need it!” and figure out the answer in your head? (Spoiler: It does!) Not to mention knowing how to mentally solve small, simple math problems can save you some steps and help you out if you do need to solve a more complicated, difficult problem. There are always going to be some math problems that it would be silly to not solve with a calculator, but, yes, mental math is useful. And if you’re wondering if math itself is useful, math lessons you’ll actually use in real life.
Step-by-step explanation:
Compare: -7 -4
PLEASE HELP ME!
10
-25 please answer
Answer:
(-15)
Step-by-step explanation:
10-25 = (-15)
Please follow me and mark as brainliest
An automatic teller machine gives you $150 in five and ten-dollar bills. There are two more than twice as many five-dollar bills as there are ten-dollar bills. How many of each denomination are there?
Answer:
There are 7 ten-dollar bills and 16 five-dollar bills.
Step-by-step explanation:
Let's call:
T: Number of ten-dollar bills
F: Number of five-dollar bills
The amount of money withdrawn from the ATM is $150:
10T+5F=150
Dividing by 5:
[tex]2T+F=30\qquad\qquad [1][/tex]
We also know there are two more than twice as many five-dollar bills as there are ten-dollar bills:
[tex]F=2+2T\qquad\qquad [2][/tex]
Substituting [2] into [1]:
2T+2T+2=30
Rearranging:
2T+2T=30-2
Simplifying:
4T=28
Solving:
T=28/4=7
From [2]:
F=2+2*7=2+14=16
There are 7 ten-dollar bills and 16 five-dollar bills.
Which shows another way to write 9.54?
O 0.5 + 0.04
O 9+ 0.4 + 0.05
O (9 * 1) + (5 x 0.1) + (4 x 0.01)
O (9 x 0.1) + (5 x 0.01) + (4 x 0.001)
Answer:
It would be C
Step-by-step explanation:
What is this expression equivalent to? Will Give Brainliest! Image is below.
Answer:
the correct answer is 4
An experiment consists of determining the speed of automobiles on a highway using a radar equipment. The random variable in this experiment is a:
Answer:
the speed value that the radar equipment outputs.
Step-by-step explanation:
A random variable in an experiment is also (and most times the case) called a dependent variable. In this scenario, the random variable would be the speed value that the radar equipment outputs. This is because this value depends on the actual velocity of the cars that pass by the equipment. The faster the car is moving when it passes the radar the higher value will be displayed on the equipment. Therefore, depending completely on the vehicles.
Pure acid is to be added to a 10% acid solution to obtain 99L of a 20% acid solution. which amounts of each should be used ?
Answer:
x = amount of 100% acid solution (pure acid, no water)
y = amount of 10% acid solution (acid + water)
both amounts are in liters
Step-by-step explanation:
8.032×10^-4 in standard form
Answer:
0.0008032
Step-by-step explanation:
Hope this helps!
Answer:
80,320
Step-by-step explanation:
In a certain section of Southern California, the distribution of monthly rent for a one-bedroom apartment has a mean of $2,325 and a standard deviation of $270. The distribution of the monthly rent does not follow the normal distribution. In fact, it is positively skewed. What is the probability of selecting a sample of 50 one-bedroom apartments and finding the mean to be at least $2,245 per month
Answer:
0.982
Step-by-step explanation:
Given that:
Mean (μ) = 2325
Standard deviation (σ) = 270
From the central limit theorem ; the Distribution of 50 sample means will be normally distributed
Finding the mean to be at least $2245 per month;
x = 2245
Using the Z score relation :
Zscore = (x - μ) / (σ/√n)
Zscore = (2245 - 2325) / (270/√50)
Zscore = - 80 / 38.183766
ZSCORE = - 2.0951312
= - 2.1
P(Z > - 2.1) = 0.982 ( from the Z probability Calculator).
Which 2 subjects are 2 unit apart
Answer:
I believe that your answer is C and Moon.
What does ± mean in math?
I WILL MAKE YOU A BRAINLIEST AND YOU WILL RECEIVE 50 POINTS!!!
A pharmaceutical sales representative gets paid $50,000 annually plus
3.5% commission on total sales. This year he sold $420,000 in
pharmaceuticals. What are his annual total earnings?
100% = $420,000
3.5% = 3.5/100 × 420,000
= $ 14,700
Commission he earned = $14,700
Annual total earnings= $50,000 + $14,700
= $ 64,700
Answer:
14,500
Step-by-step explanation:
Piper and her children went into a movie theater and she bought $59.50
bags of popcorn and candies. Each bag of popcorn costs $8.50 and each candy costs
$4.25. She bought 8 more candies than bags of popcorn. Graphically solve a system
of equations in order to determine the number of bags of popcorn, x, and the number
of candies, y, that Piper bought.
6 candy boxes
Step-by-step explanation :
Since they both bought their own popcorn that means they both spent $8 on popcorn making that a total of $16. Therefore we now only need to find one variable which is the number of candy boxes that they bought in order to reach the $25 total that they spent. This variable can be represented as x in the following algebraic equation.
(2*8) + 1.50x = 25
16 + 1.50x = 25 ... subtract 16 from both sides
1.50x = 9 ... divide both sides by 1.50
x = 6
Finally, we can see that Billy and Tommy bought a total of 6 candy boxes.
Answer:
This is the answer on Delta Math
Step-by-step explanation:
How is 5 represented in 6.75
Answer:
5 is in the hundreths place :))
Step-by-step explanation:
Answer:
0.05
Step-by-step explanation:
since the place value of the five is beyond the decimal point, and it is the second number beyond the decimal point, so it is in the hundredths place.
What is the equation in slope-intercept form of the line that passes through the points (−12, −4) and (4, 8)?
A. y = −43 − 20
A. , y = −43 − 20
B. y = 43 − 12
B. , y = 43 − 12
C. y = −0.75 − 13
C. , y = −0.75 − 13
D. y = 0.75x +5
D. , y = 0.75x +5
Answer:
Choice D. [tex]y = 0.75\, x + 5[/tex].
Step-by-step explanation:
The general equation for the slope-intercept form of a line in a cartesian plane is [tex]y = m\, x + b[/tex], where:
[tex]m[/tex] is the slope of the line, and[tex]b[/tex] is the [tex]y[/tex]-intercept of the line. (The [tex]y\![/tex]-intercept of a line in a cartesian plane is the [tex]y\!\![/tex]-coordinate of the point where the line intersects the [tex]\! y \![/tex]-axis.)Start by finding the value of [tex]m[/tex]. The slope of a line is equal to its rise-over-run. For the two points in this question:
The "rise" is the [tex]y[/tex]-coordinate of the first point minus that of the second: [tex]\text{rise} = (-4) - 8 = -12[/tex].The "run" is the [tex]x[/tex]-coordinate of the first point minus that of the second. The order of these two points should stay the same: [tex]\text{run} = (-12) - 4 = -16[/tex].Calculate the slope of this line:
[tex]\displaystyle m = \text{slope} = \frac{\text{rise}}{\text{run}} = \frac{-12}{-16} = 0.75[/tex].
The equation of the line becomes:
[tex]y = \underbrace{0.75}_{m}\, x + b[/tex].
Substitute the coordinates of either of the two points to find [tex]b[/tex]. For example, for the first point [tex](12, -4)[/tex], substitute in the following:
[tex]x = -12[/tex], and[tex]y = -4[/tex].The equation becomes:
[tex]-4 = 0.75 \times (-12) + b[/tex].
Solve for the value of [tex]b[/tex]:
[tex]b = 5[/tex].
Hence, the slope-intercept form of this line shall be:
[tex]y = 0.75\, x + 5[/tex].
PLEASE HELP ASAP
can you help me please
can someone tell me what my GPA is.
Answer:
probably 5.00
Step-by-step explanation:
CHECK PHOTO Intercepts of the graph BE SURE TO BE CORRECT PLEASE no work needed
Answer:
y= (0, .7)
x= (-1.2, 0)
Step-by-step explanation:
r u taking a test?
600 students are studying in a private
school, the average monthly fee of a
student is Rs. 1200. How much amount for
tax does the school pay to the government
as education service tax at the rate of 1% in
a year? *
Answer:
600 ×1200=720,000
720,000×12=8,640,000
8,640,000×1%=8,640,000÷100%=86,400
86,400 per year
you just purchased a new hooded sweatshirt for $24. the total cleaning cost is $2 total because it will be washed with other sweatshirts. you will wear the sweatshirt 18 times this winter. calculate the cost per wearing.
Answer:
Step-by-step explanation:
espera y termino y te ayudo vale que me falta poco vale
Emma is 10 years younger than Joseph. Joseph's age 6 years from
now will exceed twice Emma's age 2 years ago by 3 years.
How old is Em ma and Joseph now?
Answer:
Step-by-step explanation:
let Emma age be x now
Let Joseph age be y now
If Emma is 10 years younger than Joseph, then x = y-10
six years from now:
Emma will be x+6 years
Joseph will be y+6 years
If Joseph's age 6 years from now will exceed twice Emma's age 2 years ago by 3 years, then:
y+6 = 2(x+6-2) + 3
y+6 = 2(x+4)+3
y + 6 = 2x+11
y + 6 = 2(y-10)+!1
y + 6 = 2y-20+11
y - 2y = -9-6
-y = -15
y = 15
Since x = y -10
x = 15-10
x = 5
Hence Emma is 5years old now and Joseph is 15years old now
O SYSTEMS OF EQUATIONS AND MATRICES
Solving a word problem using a 3x3 system of linear equations....
Over the last 3 evenings, Latoya received a total of 96 phone calls at the call center. The second evening, she received 2 times as many calls as the third
evening. The third evening, she received 8 fewer calls than the first evening. How many phone calls did she receive each evening?
Answer:
Find the midpoint of the line segment joining the points R(,) and S(,).
Step-by-step explanation:
Express 610.47 in unit form.
Answer:
6 hundreds
1 tens
0 ones
4 tenths
7 hundredths
7
Felicia is making trail mix. The recipe calls for 3 cups pretzels and 1.5 cups of m&m's.
She wants to make 27 cups of trail mix for a birthday party. How many cups of pretzels and m&m's does she need?
Answer:
81 Cups of Pretzels and 40.5 Cups of M&M's
Step-by-step explanation:
p= Pretzels
m= M&M;s
3p+1.5m= 1
3(27)+ 1.5(27)
81 + 40.5
If paper clips are 7/8 of an inch long and cost $0.02 to make, how much would it cost to produce enough paper clips to make a line, end to end, that stretches 56 inches?
Answer:
$1.12
Step-by-step explanation:
When you multiply 8/7 of 56, you get 64.
This shows that you will need 64 paperclips to make 56 inches worth of paper clips. If each paper clip costs two cents, you need to multiply 56 paperclips by 2 cents. 56x0.02=1.12 so it will cost you 1 dollar and twelve cents
Solve the following equation algebraically. Show your work.
6=x+23
Answer: 23+x=6
-23 -23
1x/1 -17/1
x=-17
Step-by-step explanation:
Answer:
Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :
-6*x-(23)=0
Step by step explanation :
Pulling out like terms
Pull out like factors :
-6x - 23 = -1 • (6x + 23)
Solving a Single Variable Equation:
2.1 Solve : -6x-23 = 0
Add 23 to both sides of the equation :
-6x = 23
Multiply both sides of the equation by (-1) : 6x = -23
Divide both sides of the equation by 6:
x = -23/6 = -3.833
Therfor the answer is : x = -23/6 = -3.833
What is the z-score for Paula If she got 1400 on the SAT, the mean was 1100 and the
standard deviation was 275?
Which series of transformations would result in a figure that is congruent to the triangle ABC?
rotation of 180' clockwise about the origin and then dilation with a scale factor of -1, centered at the origin
rotation of 180' clockwise about the origin and then dilation with a scale factor of 2, centered at the origin
reflection across the line y ox and then dilation with a scale factor of -3, centered at the origin
translation 3 units to right and then dilation with a scale factor of 3, centered at the origin
Answer: rotation of 180' clockwise about the origin and then dilation with a scale factor of -1, centered at the origin
Step-by-step explanation:
Two triangles are congruent if all the corresponding angles are equal, and if the corresponding side lengths are equal.
Now, this means that if we have a given triangle, and we apply a dilation/contraction, then the resultant triangle will have different side lengths than the initial triangle, then those two triangles can not be congruent.
So we can already discard all the options with dilations.
Now, remember how the dilation works.
If we have a point that is at a distance L of the origin, and we do a dilation of scale factor K centered at the origin, then the new distance of the point and the origin will be K*L.
Notice that if the scale factor is equal to 1, then there is no change.
In the options, we have one where the scale factor is -1.
The minus sign means that will cause the enlargement to appear on the other side of the center of enlargement. But the scale factor still is of absolute value 1, so it will not change anything.
Then the only option that not dilates the triangle is:
Rotation of 180' clockwise about the origin and then dilation with a scale factor of -1, centered at the origin
So this is the only transformation that results in a figure congruent to the triangle ABC